<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>字符串</title>
    <script src="index.js"></script>
    <link rel="stylesheet" href="home.css">
</head>
<body>
    <button type="button" onclick="myFuction()">字符串</button><br/>
    <button type="button" onclick="operateString()">操作字符</button><br/>
    <button type="button" onclick="toUpperCase()">字符串变大</button><br/>
    <button type="button" onclick="toLowerCase()">字符串变小</button><br/>
    <button type="button" onclick="indexOf()">搜索字符串出现的位置</button><br/>
    <button type="button" onclick="subString()">返回指定索引区间的字符串</button>

</body>
</html>